package org.example.utils;

import cn.hutool.core.lang.UUID;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;

import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements ILock{

    private String name;
    private StringRedisTemplate stringRedisTemplate;

    public SimpleRedisLock(String name,StringRedisTemplate stringRedisTemplate)
    {
        this.name=name;
        this.stringRedisTemplate=stringRedisTemplate;
    }
    private static final String KEY_PREFIX="lock:";
    private static final String ID_PREFIX= UUID.randomUUID().toString(true)+"-";
    private static final DefaultRedisScript UNLOCK_SCRIPT;
    static {
        UNLOCK_SCRIPT=new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }
    @Override
    public boolean tryLock(long timeoutSec) {
        //获取线程标识
        String threadId = ID_PREFIX+Thread.currentThread().getId();
//        获取锁
        Boolean success = stringRedisTemplate.opsForValue()
                .setIfAbsent(KEY_PREFIX + name, threadId, timeoutSec, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(success);
    }
    @Override
    public void unlock(){
        //调用lua脚本
        stringRedisTemplate
                .execute(UNLOCK_SCRIPT,
                        Collections.singletonList(KEY_PREFIX+name),
                        ID_PREFIX+Thread.currentThread().getId());

    }
}
